Applications with devices to which this disclosure relates are known in various types of textile machine. Precise and delicate patterns and figures are becoming more and more in demand in the production of fabrics and/or carpets. The yarns are sub-divided into ever smaller groups and are together fed and/or selected by a pattern-controlled component in order to obtain the desired result in the fabric and/or carpet. The yarns are even being increasingly individually controlled and/or selected. This leads to a sharp increase in the number of actuators used.
Different versions of such pattern-controlled components can be found in tufting machines. Pattern-controlled components known as “pile feeders” are provided to feed the yarn pattern driven to the tufting needles. Other pattern-controlled components such as pattern-controlled components that control the hooks under the tuft fabric, with or without knives, are provided to determine the pattern-controlled selection of the pile height and/or pile form, namely pile loops or cut pile. Further pattern-controlled components which control the tufting needles directly are provided for the pattern-controlled selection of the yarn to be brought into a base fabric.
A Jacquard machine is equipped with a very large number of pattern-controlled components for pattern-controlled positioning of the yarn. A weaving machine can comprise a Jacquard machine. A weaving machine can also be equipped with pattern-controlled components provided to feed the yarn pattern driven in order in this way to determine the pile height of the piles in the carpet.
In the case of Axminster weaving machines the pattern-controlled components can be provided for pattern-controlled selection of the yarn to be brought into a fabric. Such an Axminster weaving machine then comprises an Axminster Jacquard machine with such pattern-controlled components provided for pattern-controlled selection of the yarn.
The actuators used here can be rotary motors, linear motors, stepper motors, voice-coil actuators, hydraulic or pneumatic actuators, solenoids, etc.
In the different types of textile machines, a large number of these pattern-controlled components are installed in a limited space in the above-mentioned devices. An arrangement often comprises dozens, hundreds or even thousands of actuators. The actuators thereof must hereby be capable of being cooled in an efficient manner.
Today, these actuators are usually cooled with air.
U.S. Pat. No. 6,807,917 B1 describes an example of such a device with yarn feeding modules for feeding yarn into a tufting machine in which the motors are air-cooled. Here a series of fans direct the necessary air over the components to be cooled.
Air as a coolant is less effective, however, than other known cooling fluids. In the area around textile machines, the ambient air is warm and dusty so that filters are necessary to remove the dust from the air. Another possibility is to use outside air as cooling air, but this solution requires additional air pipes. Furthermore, in both cases a large contact area is necessary between the actuators and the air in order to be able to dissipate sufficient heat, and a relatively large flow of air is necessary in order to be able to cool the actuators sufficiently.
In order to overcome the disadvantages of cooling with air, attempts are already being made to cool these actuators with water.
US 2008/0178960 A1 and FR2 944 808 A1 describe a few examples of how motors for a shed forming device can be designed for water cooling.
A major disadvantage here, however, is that in the event of a defect in an actuator so that it has to be replaced, the cooling circuit in which the water is flowing has to be interrupted. This results in the replacement of an actuator being fairly burdensome and time-consuming. Furthermore, the water from the cooling circuit can cause considerable damage in a textile machine.
Such water-cooled actuators are already in use in applications on textile machines with a limited number of actuators installed alongside or under the actual working area of the textile machine, namely the yarn feeding and textile forming zone. The failure percentage of the actuators is relatively limited there and the risks of an interruption of the cooling circuit are more limited there, since the actuators are installed outside the actual working area. In applications to which this invention relates in which dozens, hundreds or even thousands of actuators are installed in a more limited area in the immediate vicinity of the actual working area of the textile machine, and then predominantly above it, however, such water-cooled actuators are barely employed in practice. Due to the large number of actuators, there is a real chance of failure of one of the actuators, and furthermore the risks of consequential damage from the interruption of a water-filled cooling circuit cannot be neglected.